A complementary processes account of the development of childhood amnesia and a personal past

Personal-episodic or autobiographical memories are an important source of evidence for continuity of self over time. Numerous studies conducted with adults have revealed a relative paucity of personal-episodic or autobiographical memories of events from the first 3 to 4 years of life, with a seemingly gradual increase in the number of memories until approximately age 7 years, after which an adult distribution has been assumed. Historically, this so-called infantile amnesia or childhood amnesia has been attributed either to late development of personal-episodic or autobiographical memory (implying its absence in the early years of life) or to an emotional, cognitive, or linguistic event that renders early autobiographical memories inaccessible to later recollection. However, neither type of explanation alone can fully account for the shape of the distribution of autobiographical memories early in life. In contrast, the complementary processes account developed in this article acknowledges early, gradual development of the ability to form, retain, and later retrieve memories of personally relevant past events, as well as an accelerated rate of forgetting in childhood relative to adulthood. The adult distribution of memories is achieved as (a) the quality of memory traces increases, through addition of more, better elaborated, and more tightly integrated personal-episodic or autobiographical features; and (b) the vulnerability of mnemonic traces decreases, as a result of more efficient and effective neural, cognitive, and specifically mnemonic processes, thus slowing the rate of forgetting. The perspective brings order to an array of findings from the adult and developmental literatures.